Saturday, February 25, 2017

Vole tunnels

 We'd lost almost all of our snow over the last week.  The streams were high and the swamps were doing their best to take up the overflow.  But it's still only February so the weather was bound to change.  We had plenty of notice - there were storm warning banners running at the bottom of the TV for two days prior.  Friday the snow came.
Here we got only a little bit - the worst of the storm went to the south.  Indy and I went out to investigate once the winds died down today. These are vole tunnels.  Voles are at the bottom of food chain (as far as mammals go) so they do whatever they can to stay hidden while on their travels.  Much easier to do when there is a foot of snow then under these mere two inches.

Friday, February 24, 2017

Lepidolite

The typical violet to pink color is characteristic of Lepidolite.   It is not only the most abundant lithium-bearing rock but also a major source of the rare alkali metals rubidium and cesium.  Since Lepidolite is a member of the mica group it is also sometimes called Lithia Mica.  Hardness is 2.5 to 4.

Thursday, February 23, 2017

Ulexite

Ulexite is one of the rare borate minerals.   Boron is a trace element of Earth's crust and borates form under only one condition - in drainage basins from fragments of rocks erupted by volcanoes.  Ulexite looks like it's made up of closely-packed fibrous crystals.  Small polished pieces will transmit an image from one side to the other like fiber-optics.  That optical phenomena gave Ulexite a nickname of "TV rock".  Hardness is 2.5

Wednesday, February 22, 2017

Unakite

Unakite (hardness 6 to 7) is a metamorphic rock created when granite is altered by hydrothermal activity.   It is known for it's peach colored feldspar spots, pistachio green epidote, and clear quartz.   While it usually isn't used in commercially made jewelry, it's a favored stone in craft jewelry.  It's also used in some architectural settings such as the Smithsonian Natural History Museum.  Slabs of unakite trim the front steps and are used as floor tiling on the entrance landing.

Tuesday, February 21, 2017

Jade

There are two minerals that are called "jade".  The blue jade I posted earlier is jadeite.  These examples are nephrite.  That's about it for jade.

Monday, February 20, 2017

Aragonite

What do pearls and Tums antacids have in common?  They are made from the same substance Aragonite is from - calcium carbonate.  Aragonite is another element not stable at low pressures and temps but does form due to "magnesium poisoning".  Solutions which are supersaturated w/ calcite can't precipitate if there is also a high concentration of magnesium thus allowing aragonite crystals to form.  Argonite can form in delicate crystals or in horizontal layers (like this example) and has a hardness of 4.

Sunday, February 19, 2017

Sunset clouds

Still nice weather so more long walks w/ Indy.  I'm reading a book on a dog's ability to smell.  I watch w/ a new interest as her nose checks out all sorts of things.  Tall dead grasses along the path which probably tell her about the coyotes that passed that way.  She buries her nose into the snow - can she smell the voles which have paths just under the remaining remnants of snow?  I use my walking stick to point out a small hole dug into the hay field.  She obediently comes and sniffs at it but quickly loses interest.  I look into the hole and see it is full of water.  Guess it was last year's den for something.  She stops and lifts her head into the air.  She smells something far off down in the swamp.  However, we can't go that way yet and I turn back into the woods.  She follows me.  No matter how tempting the scent might be best to stay w/ the pack.

A Story in the Snow

This is the weekend for the yearly Great Backyard Bird Count.  It started on Friday and goes through Monday.  Coincidentally we've been having above freezing temps so the snow has melted to bare ground/just a cover/small drifts of two feet.  Indy and I took off walking each day through fields, woods, and swamp.  After an hour I saw only three crows on Friday and one crow on Saturday.  However, was able to follow some tracks.  This picture is one of a chase.  I followed rabbit tracks across an open area down to the frozen surface of Gorgeous Gorge.  They were widely spaced so it looked like the rabbit was going full speed.  Tracking along beside were coyote paw prints.  As soon as the rabbit tracks reached the flat ice, they did a quick turn back up across the dam.  The coyote tracks went past them, looped around, and came back to follow the rabbit again.  Coyote couldn't make the turn as fast as the rabbit?  Followed the tracks into a nearby blackberry thicket where (a) I wasn't going to follow and (b) they were lost among the deer tracks that made a often used path along the edge of the vines.  I'm no tracking expert so the story might not have gone down the way I think.  Just another way I have fun in the winter.

Friday, February 17, 2017

Astrophyllite

Not a stone you usually see.  While there are some specimens made into jewelry, it's a rare mineral that is only of interest to scientists and collectors.  It is a form of Muscovite distinct because of the radiating crystal structure.  Note that astrophyllite has absolutely nothing in common w/ the mineral of the same name mentioned in Rock Hunter's 2015 book about the Roman Catholic Catechism where he says a piece of this mineral can be broken off and it will continue to "live" and grow.

Thursday, February 16, 2017

Pietersite

Also known as "Tempest Stone".   Breccaited is your word for this week.  It comes from the Italian word for "loose gravel".  Brecca refers to any rock that is composed of broken fragments of other rocks that then meld together.  Pietersite is made up of pieces of golden tiger's eye and blue hawk's eye cemented together by quartz.   As w/ many geological formations, this one also is controversial.  Some geologists say it is not a tiger's eye/hawk's eye blend but a chalcedony embedded w/ amphibole fibres which gives it the chatoyancy (remember that was the word from last week).  The conflict could be caused because there are two places mining Pietersite.   This rock came from a mine in the Kunene region of Namibia.  The other site for Pietersite is in Hunan, China (that mine became flooded and hasn't been operational for years).  The rocks from the two sites vary a little in composition.  It has a hardness of 7.

Wednesday, February 15, 2017

Tiger Iron

Tiger Iron has a hardness of 7 and is often used for inlays from knife hilts to furniture.  It is made up of undulating layers of golden tiger eye, hematite, and red jasper.  There are a couple ideas of how tiger iron was formed.  Could be that the different layers of sediment were laid down and over the years of heat and pressure metamorphosed into this stone.  Another idea suggests that tiger iron is stromatolites (fossilized algae).  Sediment sticks to mats of microbes living on the ocean floor forming a crust.  A new layer of algae forms on top of that layer, etc.  This results in gentle mounding where a cross section shows each successive layer.   Could be it's a combination of both processes.  What I find interesting is that there is so little known or written about many geological formations.  However, on the Internet, there are literally hundreds of sites cataloging each mineral's "ability" to impart to it's owner the qualities of joy, peace, healing, prosperity, etc.  Similar to the differences between astronomy and astrology.

Tuesday, February 14, 2017

Ruby in Zoisite

The pinkish portion of the mineral is ruby,  the green is zoisite, and the black hornblende.  This particular combination is sometimes called anyolite and was first found in 1954 in Tanzania.  While the ruby is chemically real ruby, it isn't gem quality. A stone like this made news in the UK 10 years ago.   In 2007 the Wreken Construction Company was bought.  By 2009 though the company was insolvent and their books audited. It was found the biggest asset used in financing the company since the 2007 sale was a 10,000 carat uncut ruby called The Gem of Tanzania.  Papers w/ the stone showed it had been valued at 17 million dollars by an Italian gem company. Closer checks though revealed that paperwork was forged and the raw ruby was an Anyolite (similar to this one but 4 lbs heavier) - value $160.  The Gem of Tanzania was offered for sale in the Rock 'n Gem - a quarterly magazine read by mineral collectors and psychic devotees.  Maybe because of it's unique provenance, it eventually sold for $8,000.

Monday, February 13, 2017

Rose Agate

This agate was the closest I could come to being "valentine" themed.  It's almost 6 p.m. but enough twilight and bright snow that I can watch deer feeding in the meadow.  The snow may not last much longer - forecast for the rest of this week is above freezing temps.  It's about this time of year that people in the Northwoods start looking for any tiny glimmer that spring is on it's way.  February is way too early and we are always disappointed by another deep freeze or blizzard.  Probably that's what makes us hopeful, stalwart, pragmatic, and dowright giddy when spring does arrive.

Sunday, February 12, 2017

Moonlight on snow

I've been thinking about this month's photo project.  February is "happy".  Each person in the contest puts 5 pictures they have taken out on our designated blog site which embody the word of the month.  It's certainly not that I'm an unhappy person but it isn't something I have in mind when I take photos.  (Makes this kind of contest challenging though.)  I did take a picture of Indy out on one of our walks. Her tongue is hanging out on one side and she's looking up at me.  Tell me, what dog doesn't look happy?  Also have a pic of Orion.  She's laying on the back of a stuffed chair in the sun looking at me. That's as good as it gets for her so will label that picture "This IS my happy face."  Meanwhile I've been making notes of other ideas: coffee and chocolate candy, a Shakespeare sonnet, the bathtub filled w/ bubbles, jigsaw puzzle, etc.

Saturday, February 11, 2017

Lunar eclipse

As eclipses go, last night's wasn't a great one.  The moon went through the penumbra portion of earth's shadow and not the darker umbra.  The moon looks a bit darker on one side than the other but that's about it.   I haven't been taking many pictures this time of year so it was fun to be on the deck w/ the tripod.  A pack of coyotes were howling in the dark just past me at Gorgeous Gorge.  The moon was shining off the shiny crust of the snow in the field.  The ski hill was all lit up.  Wasn't even all that bad temp-wise, maybe in the 20's.  Nice night considering everything.